Collaboration between users often includes verifying that they are in sync with respect to information that is being passed between them. In an online tutorial, for example, an instructor can present illustrative examples that the student is expected to follow along with. It is important to know that both the instructor and the student are looking at the same information. In a technical support situation, where the technical support is being provided remotely, it is important to be able to verify that the user is following instructions given to the user to configure or otherwise affect the user's computer. In situations such as these, verification of the state of the user's computer (e.g., do they have the same lesson plan, have they executed the commands given by tech support) can be performed at certain points in time during the interaction so that corrective action, if any, can be taken before proceeding with the interaction.
The verification effort can be time-consuming. For example, if a lesson plan involves the student following the instructor in a long series of data entries (e.g., running through an example in a spreadsheet application, running through a sequence of menu operations on an application, etc.), the verification process can require both the instructor and the student to review all the data entries, just to determine whether there is an error or not.